Application of immuno-PCR assay for the detection of serum IgE specific to Bermuda allergen

Investigating allergen-specific IgE distribution and correlations in chronic urticaria: a retrospective study in Shanghai, China

BACKGROUND

Chronic urticaria (CU) is a persistent skin condition characterized by recurring episodes triggered by diverse allergens and a multifaceted causative nature. The present study aimed to retrospectively explore the distribution patterns and correlations of specific IgE (sIgE) antibodies with various allergens among patients with CU.

METHODS

For this purpose, the present study enrolled 820 patients with CU treated at Shanghai Skin Disease Hospital from July 2020 to September 2023. Serum samples were assessed for allergen sIgE antibodies via an immunodiagnostic assay. Chi-square tests were used to examine the differences in allergen sIgE antibody distribution across the sex and age groups. Spearman's correlation analysis was used to investigate the correlations between different allergens.

RESULTS

Among the 820 patients with CU, 705 presented positive results for at least one sIgE antibody. Concerning sex, no significant disparities were observed in food allergen distribution; however, males presented notably higher storage mites and Aspergillus levels than females. Age stratification revealed that adolescents had significantly higher positivity rates for milk, egg yolk, house dust mites, storage mites, cat and dog dander, and timothy grass than adults and elderly patients. The correlation coefficient between house dust mites and storage mites reached 0.81. However, correlations among distinct food allergens mostly remained below 0.3, barring sesame and mixed fruits, which was a weak correlation (r = 0.31). The correlations between food and inhaled allergens ranged from 0.3 to 0.5, suggesting a relatively weak association.

CONCLUSIONS

There were no sex disparities in the distribution of ingestible allergens, yet adolescents presented higher positivity rates than the other age groups. The associations among food allergens, as well as food and inhaled allergens, were relatively weak. Trial registration Retrospectively registered.

Ultrasensitive reporter DNA sensors built on nucleic acid amplification techniques: Application in the detection of trace amount of protein

The detection of protein is of great significance for the study of biological physiological function, early diagnosis of diseases and drug research. However, the sensitivity of traditional protein detection methods for detecting trace amount of proteins was relatively low. By integrating sensitive nucleic acid amplification techniques (NAAT) with protein detection methods, the detection limit of protein detection methods can be substantially improved. The DNA that can specifically bind to protein targets and convert protein signals into DNA signals is collectively referred to reporter DNA. Various NAATs have been used to establish NAAT-based reporter DNA sensors. And according to whether enzymes are involved in the amplification process, the NAAT-based reporter DNA sensors can be divided into two types: enzyme-assisted NAAT-based reporter DNA sensors and enzyme-free NAAT-based reporter DNA sensors. In this review, we will introduce the principles and applications of two types of NAAT-based reporter DNA sensors for detecting protein targets. Finally, the main challenges and application prospects of NAAT-based reporter DNA sensors are discussed.

Immunoproteomics Methods and Techniques

The varied landscape of the adaptive immune response is determined by the peptides presented by immune cells, derived from viral or microbial pathogens or cancerous cells. The study of immune biomarkers or antigens is not new, and classical methods such as agglutination, enzyme-linked immunosorbent assay, or Western blotting have been used for many years to study the immune response to vaccination or disease. However, in many of these traditional techniques, protein or peptide identification has often been the bottleneck. Recent progress in genomics and mass spectrometry have led to many of the rapid advances in proteomics approaches. Immunoproteomics describes a rapidly growing collection of approaches that have the common goal of identifying and measuring antigenic peptides or proteins. This includes gel-based, array-based, mass spectrometry-based, DNA-based, or in silico approaches. Immunoproteomics is yielding an understanding of disease and disease progression, vaccine candidates, and biomarkers. This review gives an overview of immunoproteomics and closely related technologies that are used to define the full set of protein antigens targeted by the immune system during disease.

Comparative diagnostics of allergy using quantitative immuno-PCR and ELISA

AIM

Estimation of specific IgE is essential for the prevention of allergy progression. Quantitative immuno-PCR (qiPCR) can increase the sensitivity of IgE detection. We aimed to develop qiPCR and compare it to the conventional ELISA in identification of IgE to Alt a 1 and Fel d 1 allergens.

RESULTS

Single stranded 60-mer DNA conjugated to streptavidin was used to detect antigen-IgE-biotin complex by qiPCR. In semi-logarithmic scale qiPCR data were linear in a full range of serum dilutions resulting in three- to ten-times higher sensitivity of qiPCR in comparison with ELISA in IgE estimation in low titer sera.

CONCLUSION

Higher sensitivity of qiPCR in identification of low titer IgE is a result of a higher linearity of qiPCR data.

Immuno-PCR, a new technique for the serodiagnosis of tuberculosis

Rapid and accurate diagnosis of tuberculosis (TB) is essential to control the disease. The conventional microbiological tests have limitations and there is an urgent need to devise a simple, rapid and reliable point-of-care (POC) test. The failure of TB diagnostic tests based on antibody detection due to inconsistent and imprecise results has stimulated renewed interest in the development of rapid antigen detection methods. However, the World Health Organization (WHO) has emphasized to continue research for designing new antibody-based detection tests with improved accuracy. Immuno-polymerase chain reaction (I-PCR) combines the simplicity and versatility of enzyme-linked immunosorbent assay (ELISA) with the exponential amplification capacity and sensitivity of PCR thus leading to several-fold increase in sensitivity in comparison to analogous ELISA. In this review, we have described the serodiagnostic potential of I-PCR assays for an early diagnosis of TB based on the detection of potential mycobacterial antigens and circulating antibodies in body fluids of TB patients.